Officials say the move is precautionary after a gunman killed three children and a rabbi at a religious school in France.

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A father and his two sons were among four people who died Monday when a gunman opened fire in front of a Jewish school in a city in southwest France.

The NYPD has added extra security patrols in front of Jewish schools and community centers after a gunman overseas targeted children entering a religious school.

NYPD officials said there is no specific threat in New York, but there is always a concern of possible copycat or lone-wolf attacks here.

"We put in additional coverage in our critical response vehicles, at synagogues and Jewish locations in the city," Police Commissioner Ray Kelly said Monday. "We don't know if something happens in Europe, can impact on us here."

"We have a significant Jewish population in this city, and we have to take that into account," he added.

The security measures across the city come after a gunman opened fire in Toulouse, France Monday, killing three Jewish children and a rabbi. The shooter then fled on a motorbike.

The shooting at the school happened days after two similar incidents in which a man on a motorbike shot and killed three French soldiers in Montauban and Toulouse.

French authorities said they believe the shootings are linked and are being investigated as possible terror attacks. Ballistic tests are not yet complete but the same weapon may have been used in all three incidents, officials said.

The rabbi – identified in overseas press accounts as Jonathan Sandler -- and two of his children along with a third child were killed at Ozar Hatorah school. French President Nicolas Sarkozy visited the scene and condemned the attack.

The gunman remains on the loose and officials fear he may be looking to strike again. French officials have beefed up patrols across the Toulouse region.

In New York, extra NYPD vehicles could be seen stationed outside the Park East Synagogue, Temple Emanu-El, Israeli Mission, Yeshiva University, the Jewish Theological Seminary and Lubavitch World Headquarters, among other Jewish institutions.

Anti-Defamation League Director Abraham Foxman expressed outrage over the shootings of the French children on their way to school.

"There can be no justification or excuse for such a barbaric, hate-filled and brutal crime," Foxman said.

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